Herlev-Gentofte University Hospital, Medical Department O, Respiratory Section; Herlev-Gentofte University Hospital, Department of Cardiology, Copenhagen, Denmark
The Copenhagen Male Study Epidemiological Research Unit, Departments of Occupational and Environmental Medicine, Bispebjerg University Hospital; The Copenhagen City Heart Study, Frederiksberg Hospital, Copenhagen, Denmark.
Thorax. 2019 Sep;74(9):843-848. doi: 10.1136/thoraxjnl-2018-212821. Epub 2019 Jun 17.
Good midlife cardiorespiratory fitness (CRF) may reduce the risk of chronic obstructive pulmonary disease (COPD). Reverse causation may play a role if follow-up time is short. We examined the association between CRF and both incident COPD and COPD mortality in employed men with up to 46 years follow-up, which allowed us to account for reverse causality.
Middle-aged men (n=4730) were recruited in 1970-1971. CRF was determined as VOmax by ergometer test. Categories of CRF (low, normal, high) were defined as ± 1 Z-score (± 1 SD) above or below the age-adjusted mean. Endpoints were identified through national registers and defined as incident COPD, and death from COPD. Multi-adjusted Cox models and restricted mean survival times (RMST) were performed.
Compared with low CRF, the estimated risk of incident COPD was 21% lower in participants with normal CRF (HR 0.79, 95% CI 0.63 to 0.99) and 31 % lower with high CRF (HR 0.69, 95% CI 0.52 to 0.91). Compared with low CRF, the risk of death from COPD was 35% lower in participants with normal CRF (HR 0.65, 95% CI 0.46 to 0.91) and 62% lower in participants with high CRF (HR 0.38, 95% CI 0.23 to 0.61). RMST showed a delay to incident COPD and death from COPD in the magnitude of 1.3-1.8 years in normal and high CRF vs low CRF. Test for reverse causation did not alter the results.
In a population of healthy, middle-aged men, higher levels of CRF were associated with a lower long-term risk of incident COPD and death from COPD.
良好的中年心肺适能（CRF）可能降低慢性阻塞性肺疾病（COPD）的风险。如果随访时间较短，可能会出现反向因果关系。我们研究了在随访时间长达 46 年的中年男性中，CRF 与新发 COPD 和 COPD 死亡率之间的关系，这使我们能够考虑到反向因果关系。
1970-1971 年招募了中年男性（n=4730）。CRF 通过测功计试验确定为 VOmax。CRF 类别（低、正常、高）定义为年龄调整均值上下±1 Z 分数（±1 SD）。通过国家登记册确定终点，并定义为新发 COPD 和 COPD 死亡。多因素调整 Cox 模型和限制性平均生存时间（RMST）进行了分析。
与低 CRF 相比，正常 CRF 参与者新发 COPD 的风险估计降低了 21%（HR 0.79，95%CI 0.63-0.99），高 CRF 参与者降低了 31%（HR 0.69，95%CI 0.52-0.91）。与低 CRF 相比，正常 CRF 参与者 COPD 死亡的风险降低了 35%（HR 0.65，95%CI 0.46-0.91），高 CRF 参与者降低了 62%（HR 0.38，95%CI 0.23-0.61）。RMST 显示，与低 CRF 相比，正常和高 CRF 组新发 COPD 和 COPD 死亡的时间分别延迟了 1.3-1.8 年。反向因果检验并未改变结果。
在健康的中年男性人群中，较高的 CRF 水平与长期新发 COPD 和 COPD 死亡风险降低相关。
